Children who are hard of hearing (HH) have mild through moderately severe hearing loss. These children are at-risk for long-term developmental difficulties due to limitations in their access to the auditory information in their world and in particular limitations in their access to spoken communication. Many of these children now receive clinical hearing and speech/language services to address this risk; however there has been very little research that focused on these children. This research gap was addressed during the current funding period with a large cohort of preschool-aged HH children via the Outcomes of Children with Hearing Loss (OCHL) project. Our research to date indicates that some children and some domains of development are more susceptible than others to the presence of mild to severe hearing during the preschool years. Vulnerabilities were most evident in areas dependent on processing fine details in the linguistic input, including syntax, grammatical morphology, phonology, and meta-phonological skills. Vocabulary and pragmatic language skills (related to social cognition) also showed effects of hearing loss. Additionally, we have identified systematic effects of degree of hearing loss on speech and language outcomes, as well as the protective effects of aided audibility on these outcomes. From this work, we have begun to construct an account of the basis for the observed variability in outcomes of HH children as well as its impact on development. The proposed research will extend this inquiry into the early school years. Our aims in this research concern whether the communication vulnerabilities we have seen in the preschool years persist into the school years and contribute to academic difficulties as well as continued communication problems. We are also interested in whether the early intervention received in the preschool years protects these children from some of the negative outcomes associated with early hearing loss. Finally, we plan to describe the special services and mainstream classroom environments these children find themselves in and whether these services and environments influence their outcomes. To accomplish this we will follow 276 HH children and 140 normal hearing (NH) classmates through 4th grade and obtain extensive information on their spoken language development and academic achievement. Additionally, for the HH children, we will obtain measures of services provided and their classroom environments during their 3rd and 4th grades. Also, of the HH children, 196 of them will have participated in our preschool longitudinal study and thus extensive information concerning hearing, speech/language services and early interventions can be associated with these school age outcomes. This study will inform theories about the consequences of inconsistent access to auditory input for developmental outcomes. Furthermore, our findings will provide empirical evidence to guide best practices by identifying early and concurrent risk and protective factors, identifying contributions of school-based interventions, and determining which children are at risk for late-emerging reading comprehension difficulties.